The present invention relates generally to molded chairs, and more particularly, to a molded chair shell having an integral support member between the seat and the back.
Molded chair shells have been well known in the art for some time. A typical example of a molded chair shell is disclosed in U.S. Pat. No. 3,669,496, which includes a single, molded piece that forms the seat and the seat back. The chair further requires a frame, i.e., a back support, to which the molded piece is attached.
Another example of a molded chair is disclosed in U.S. Pat. No. 3,751,109, which shows a single, molded piece with legs attached at the bottom. This chair does not have a back support and therefore may be prone to material failure. Specifically, when a user sits in the chair and exerts a force on the back portion by leaning back on the back portion, the stress and strain resulting from the force will be concentrated primarily in the area that joins the seat to the back of the chair. Thus, after repeated use, this area ultimately may be prone to material failure. In such a situation, the back portion may not provide adequate support due to the degradation of the material joining the seat to the seat back, or in extreme cases, the back portion may ultimately break away from the seat portion.
There is thus a need for a molded chair shell that does not require an external frame to provide back support, which delays material failure, and has an increased life-span over prior art designs.